As an example of display drive circuits, there is an LC drive circuit for driving an LC display. In recent years, e.g. battery-driven information devices and mobile phones are equipped with compact LC displays. Such compact LC displays are strongly required to achieve high definition, low cost, low power consumption, etc. To meet such requirements, measures, including the enhancement of the passband property of a color filter, are taken. A downside of this is that the color purities of primary colors R(Red), G(Green) and B(Blue) are lowered, and thus the range of colors (color gamut) which an LC display panel can express is narrowed. Therefore, compact LC displays tend to decline in its capability of expressing colors.
Under such circumstances, an attempt has been made to emphasize the saturations of data to be displayed on an LC display thereby to widen the apparent color gamut and enhance the capability of expressing colors as much as the LC display panel can express. For example, a technique to solve the problem of color gradation deterioration and the like attributed to the phenomenon that the saturation comes after expansion has been known, which is disclosed by e.g. Japanese Patent No. 3,749,722. Applying the technique to compact LC display panels, the apparent color gamut can be widened thereby to increase the capability of expressing colors as much as the panels can express.